According to unofficial sources, Petar Ćosić aka Šarac and Manuel Vulić are suspected of killing Milovac.
USKOK anti-corruption office deputy head Željka Panza Ostrogonac said six criminal groups had been under investigation in two separate cases.
All criminal groups were high-profile gangs and the arrested Croatian nationals held high positions in them, she said.
Panza Ostrogonac said that the arrest of Serbian drug lord Darko Šarić in Belgrade on Thursday had some connection to the charges regarding the murder of Milovac, a Croatian national, in Ecuador.
Without revealing the suspects’ identity, the prosecutorial authorities said earlier that an investigation had been launched into two groups of criminals based on a report by PNUSKOK police anti-corruption investigators and information collected in cooperation with several countries as well as EUROJUST and EUROPOL.
USKOK said that the first group of criminals consisted of ten members aged 36-63 while the other group had four members aged 29-41.
According to media reports, the 10-member group was led by Petar Ćosić aka Šarac, who in 2011 was arrested in an operation called Dogma for smuggling 339 kilograms of cocaine and was sentenced to four years in prison.
The other, four-member group, consisting of Marko Grunov, Ivan Stilinović, Tomislav Kljaić and Amer Draganović, is suspected of smuggling cocaine from Ecuador and the Dominican Republic.
The 10-member group is suspected of smuggling at least 609 kilograms of cocaine, sold for more than HRK 17 million. Some members of the group are suspected of smuggling automatic weapons, grenades, plastic explosive and pistols from Bosnia and Herzegovina to France and of smuggling 17 migrants from Croatia to Slovenia.
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